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Online Compiler, Visual Debugger, and AI Tutor for Python, Java, C, C++, and JavaScript
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<p>Python Tutor helps you do programming homework assignments in Python,
Java, C, C++, and JavaScript. It contains a unique step-by-step <a
href="visualize.html">visual debugger</a> and AI tutor to help you
understand and debug code.</p>

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Start coding online now in <a href="python-compiler.html"><b>Python</b></a>, <a href="java.html"><b>Java</b></a>, <a href="c.html"><b>C</b></a>, <a href="cpp.html"><b>C++</b></a>, and <a href="javascript.html"><b>JavaScript</b></a>
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<p>Since 2010, <b>over 15 million people in more than 180 countries</b>
have used Python Tutor to visualize over 200 million pieces of code. It
is the most widely-used program visualization tool for CS education.</p>

<p>As a preview, here is a <a href="render.html#code=def%20listSum%28numbers%29%3A%0A%20%20if%20not%20numbers%3A%0A%20%20%20%20return%200%0A%20%20else%3A%0A%20%20%20%20%28f,%20rest%29%20%3D%20numbers%0A%20%20%20%20return%20f%20%2B%20listSum%28rest%29%0A%0AmyList%20%3D%20%281,%20%282,%20%283,%20None%29%29%29%0Atotal%20%3D%20listSum%28myList%29&cumulative=false&curInstr=10&heapPrimitives=nevernest&mode=display&origin=opt-frontend.js&py=3&rawInputLstJSON=%5B%5D&textReferences=false">small example</a> showing recursion in Python:</p>

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<p>Here are some examples of how it visualizes Java, C, and C++ code:

<ul>
  <li><a href="https://pythontutor.com/articles/java-visualizer.html">How the Python Tutor visualizer can help students in your Java programming courses</a></li>
  <li><a href="https://pythontutor.com/articles/c-cpp-visualizer.html">How the Python Tutor visualizer can help students in your C or C++ courses</a></li>
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